1. Field of the Invention
The present invention relates to a tube tire including a tire mounted around the outer periphery of a rim and a tube contained in a space defined by the rim and the tire.
2. Description of Background Art
Tube tires, making use of the excellent airtightness of tubes, are generally mounted on wheels with wire spokes which are extensively used for motorcycles or bicycles.
When a radial load is applied to a wheel mounted with a tube tire, the tire and the tube are deformed by the load, and in some cases, particularly in the case where the tire rides over a rigid obstacle such as a rock or the vehicle is jumped and grounded upon off-road operation, there occurs a rim striking phenomenon in which the tube is forcibly clamped between the largely deformed tire and a metal made rim and thereby opposing areas of the inner wall surface of the tube are brought in press-contact with each other. When the opposing areas of the inner wall surface of the tube are brought in press-contact with each other by such a rim striking phenomenon, there often occurs a so called shock puncture in which the press-contact portion is pierced. In particular, as the opposing areas of the wall surface of the tube are in press-contact with each other, a portion near the rim (hereinafter, referred to as "a rim striking portion") is applied with a local load from the metal rim.
A tube tire to avoid such an inconvenience has been proposed in Japanese Patent Laid-open No. Hei 5-201213, in which a damper formed in a crescent-shape in cross section is interposed between the inner surface of a tread portion of the tire and the outer surface of the tube for preventing damage to the tube due to the rim striking phenomenon by the damper.
The above-described tube tire has a problem wherein since a damper is provided in addition to other elements, the number of parts is increased, to thereby increase the weight of the tire as well as the manufacturing cost.
In view of the foregoing, the present invention has been made, and an object of the present invention is to provide a tube tire capable of simply, effectively preventing the generation of a puncture due to contact of opposing portions of the wall surface of the tube.
In the above-described tube tire, however, the tube, when pierced by a nail or the like penetrating the buffer, is unavoidably punctured, and further, since the buffer is additionally provided, the number of parts is increased, to thereby increase the weight of the tire as well as the manufacturing cost.
In view of the foregoing, the present invention provides a tube tire capable of simply, effectively preventing the generation of a puncture due to a pierced damage to a tube by a nail or the like and of shock puncture due to riding of the tire over an obstacle.
To achieve the above object, according to the present invention there is provided a tube tire including a tire mounted around the outer periphery of a rim and a tube contained in a space defined by the rim and the tire. A double wall portion is provided at a rim striking portion of the tube, the rim striking portion is a portion brought in press-contact with the rim while putting the tire therebetween when a radial load is applied to the tire.
According to the present invention, a tube tire is provided wherein the double wall portion is a hollow structure.
According to the present invention, a tube tire is provided wherein the double wall portion has an internal space which is filled with a sealant.
According to the present invention, a tube tire is provided wherein the double wall portion is formed by sticking a rubber sheet on the outer surface of the tube.
To achieve the above object, a tube tire is provided which includes a tire mounted around the outer periphery of a rim and a tube contained in a space defined by the rim and the tire. The tube includes a peripheral wall formed in a circular shape in cross section wherein the interior of the peripheral wall is partitioned by an outer bulkhead and an inner bulkhead so that an outer sealant chamber to be filled with a sealant is defined by an outer peripheral wall constituting an outer half circumference of the peripheral wall and the outer bulkhead. An inner sealant chamber to be filled with the sealant is defined by an inner peripheral wall constituting an inner half circumference of the peripheral wall and the inner bulkhead, and an air chamber to be filled with an air is defined between the outer bulkhead and the inner bulkhead.
According to the present invention, a tube tire is provided wherein the tube integrally includes the peripheral wall, the outer bulkhead and the inner bulkhead which are formed by extrusion molding.
To achieve the above object, a tube tire includes a tire mounted around the outer periphery of a rim and a tube contained in a space defined by the rim and the tire. The tube includes a peripheral wall formed in a circular shape in cross section wherein the interior of the peripheral wall is partitioned by a bulkhead so that an air chamber to be filled with air is defined between an air chamber side peripheral wall constituting a half circumference of the peripheral wall and the bulkhead and a sealant chamber to be filled with a sealant is defined between a sealant chamber side peripheral wall constituting the remaining half circumference of the peripheral wall and the bulkhead. A buffer is interposed between the outer surface of the tube and the inner surface of the tire.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.